South 40 Wikipedia
South 40 is a popular American colloquialism with its origins in the Homestead Act of 1862. Adult heads of families were given 160 acres (0.65 km2) of public land provided they could "prove" the land by constructing a dwelling of some sort on the land and cultivating the land in some manner. After five years of residence, the deed was transferred to the homesteader. The homesteads, being 160 acres (0.65 km2), were easily divisible into quarters of 40 acres (160,000 m2) each. The south 40 would therefore refer to the south 40 acres (160,000 m2). "South 40" as a name has been used by a multitude of businesses, bands and organizations.